iPhone - UIWindow rotating depending on current orientation?

Question

I am adding an additional UIWindow to my app. My main window rotates correctly, but this additional window I have added does not rotate.

What is the best way to rotate a UIWindow according to the current device orientation?

Answer 1

You need to roll your own for UIWindow.

Listen for UIApplicationDidChangeStatusBarFrameNotification notifications, and then set the the transform when the status bar changes.

You can read the current orientation from -[UIApplication statusBarOrientation], and calculate the transform like this:

#define DegreesToRadians(degrees) (degrees * M_PI / 180)

- (CGAffineTransform)transformForOrientation:(UIInterfaceOrientation)orientation {

    switch (orientation) {

        case UIInterfaceOrientationLandscapeLeft:
            return CGAffineTransformMakeRotation(-DegreesToRadians(90));

        case UIInterfaceOrientationLandscapeRight:
            return CGAffineTransformMakeRotation(DegreesToRadians(90));

        case UIInterfaceOrientationPortraitUpsideDown:
            return CGAffineTransformMakeRotation(DegreesToRadians(180));

        case UIInterfaceOrientationPortrait:
        default:
            return CGAffineTransformMakeRotation(DegreesToRadians(0));
    }
}

- (void)statusBarDidChangeFrame:(NSNotification *)notification {

    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];

    [self setTransform:[self transformForOrientation:orientation]];

}

Depending on your window´s size you might need to update the frame as well.